1. Field of the Invention
The present invention relates to a technical field pertaining to an active matrix drive type liquid crystal device driven by thin film transistors (hereinafter referred to as xe2x80x9cTFTxe2x80x9d as necessary) or the like, a driving circuit of an electro-optical apparatus based on electroluminescence or the like, an electro-optical apparatus equipped with the driving circuit, a driving method for an electro-optical apparatus, and an electronic apparatus employing the electro-optical apparatus and, more particularly, related to a technical field pertaining to peripheral circuits such as a scanning line driving circuit and a data line driving circuit of a liquid crystal device suitably used as a light valve or the like for a liquid crystal projector.
2. Description of Related Art
Hitherto, when a liquid crystal device is employed as the light valve for this type of liquid crystal projector, there are single-chip type in which only one liquid crystal device that is colored (i.e., a color filter is formed on an opposed substrate) is employed, and multi-chip type in which three colorless (i.e., no color filter is formed) liquid crystal devices for R, G, and B, respectively, are employed. The single-chip type has a simpler constitution, however, the multiple-chip type is more advantageous in that it provides a brighter display screen and higher image quality. According to the multi-chip type, the three color light rays which have been separately light-modulated by three liquid crystal devices are compounded into a single projection light ray through a prism or dichroic mirror, then projected on a screen.
Thus, when the light rays are merged through a prism or the like, as shown in FIG. 16, for example, while light R and light B are reflected by a prism 502 after the modulation through three RGB three light valves 500R, 500G, and 500B, light G is not reflected by the prism 502. This means that the number of light inversions of light G is smaller by one. This phenomenon naturally applies when the optical system is configured such that light R or light B in place of light G is not reflected by the prism 502; this phenomenon also takes place when trichromatic light is compounded using a dichroic mirror or the like. Hence, in such a case, it is necessary to horizontally invert the display image related to light G in some form.
On the other hand, for a commercial strategic reason, there are cases where a single-chip or multi-chip type liquid crystal projector is preferably designed as a floor mounting type so that it can be installed on a floor as a typical installation and also as a hanging type which is mounted on a ceiling upside down. In this case, even for the single-chip type, it is necessary to horizontally or vertically invert the display images supplied to a liquid crystal device according to how the projector is installed. There is another case as in the liquid crystal monitor, which is a single-chip liquid crystal device, of a portable video camera where the liquid crystal is required to be inverted about, for example, a flexible joint, according to the videotaping posture of a user thereof.
Conventionally, therefore, an image signal processing IC for supplying image signals in a predetermined format to a data line driving circuit of a liquid crystal device has been used to generate and supply, for each field, an image signal for handling images obtained by vertically or horizontally inverting original pictures, e.g., only for the image signal of G or of all image signals for all colors. This is convenient because it obviates the need for adding any change to the liquid crystal device or the peripheral circuits thereof.
Or, conventionally, in the case of the multi-chip type liquid crystal projector as described above, for example, in order to compound the light rays of the three colors, a liquid crystal device in which the scanning direction is horizontally inverted as compared to the liquid crystal devices for R and the liquid crystal device for B is employed as the liquid crystal device for G.
According to the conventional method wherein the image signal processing IC is employed to vertically or horizontally invert display images as described above, however, excessive load would be placed on the image signal processing IC to respond to the recent demand for higher image quality and would be impractical.
Furthermore, the method using the liquid crystal device in which the scanning direction is inverted vertically or horizontally poses the following problems. In general, a scanning line driving circuit or a data line driving circuit has a unidirectional shift register which has a fixed direction of transfer and it is constituted so that it supplies a scanning signal or an image signal in line sequence or dot sequence according to the transfer signals generated by the unidirectional shift register thereby to perform vertical or lateral scanning on a display screen. Hence, in the case of the multi-chip type liquid crystal projector, in order to use a liquid crystal device with inverted scanning direction, it is required to fabricate two types of liquid crystal devices, namely, an R-shift type liquid crystal device having its shift register designed such that the data line driving circuit scans from left to right in relation to a display image and an L-shift type liquid crystal device having its shift register designed such that the data line driving circuit scans from right to left in relation to the display image. It is obviously disadvantageous for a manufacturer to fabricate such two types of liquid crystal devices in, for example, the manufacturing process or the like of TFT by a semiconductor manufacturing equipment or the like. Also for the users, there would be a problem in that there is no compatibility between the similar liquid crystal devices and the individual devices can be used only as their types, posing a problem in practical use. Further, the liquid crystal devices with the fixed scanning directions cannot achieve the liquid crystal monitors for the liquid crystal projectors which can be used as the floor-mounting type or the ceiling hanging type as mentioned previously or for the portable video cameras with inverting screens.
In addition, when scanning signals or image signals are supplied to a data line or a group of data lines in accordance with the transfer signals from the shift registers, preceding image signal components are written due to the superimposition or the like of preceding or following image signals supplied to an adjacent data line or an adjacent group of data lines, causing ghosts or uneven images. This problem becomes conspicuous in a high-frequency drive environment.
The present invention has been made with a view toward solving the problems described above, and it is an object of the present invention to provide a driving circuit of an electro-optical apparatus for an liquid crystal device or the like which permits easy lateral or vertical inversion of the directions of horizontal scanning or vertical scanning by using a relative simple constitution, an electro-optical apparatus equipped with the driving circuit, and electronic apparatus equipped with the electro-optical apparatus.
To solve the aforesaid problems, a driving circuit for a liquid crystal device is made as a driving circuit for an electro-optical apparatus which has a plurality of data lines to which an image signal is supplied, a plurality of scanning lines to which a scanning signal is supplied, a switching means connected to the respective data lines and the respective scanning lines, and a pixel electrode connected to the switching means; and the driving circuit is comprised of a sampling circuit for sampling and supplying the image signal to the data lines and a first bidirectional shift register which has odd number of output stages for supplying a first transfer signal to the sampling circuit; wherein the respective output stages of the first bidirectional shift register are fixed in forward direction or reverse direction in accordance with the binary level of a first direction control signal, and the first transfer signal is supplied in sequence from the respective output stages of the first bidirectional shift register in the fixed transfer direction in accordance with a first clock signal.
According to the driving circuit for the electro-optical apparatus, first, regarding data line driving means, as a first case, when a first direction control signal having one of the levels of the binary level is applied to the first bidirectional shift register from outside, the transfer direction in a first gate means provided at the respective stages of the first bidirectional shift register is fixed in the forward direction (e.g. in the direction from left to right) or the reverse direction (e.g. in the direction from right to left). Under this condition, the first transfer signal is transferred to the following stage of the first bidirectional shift register each time after the change of the binary level of the first clock signal with a predetermined cycle. Hence, the first bidirectional shift register functions as a unidirectional shift register. On the other hand, as a second case, when the first directional control signal having the other level of the binary level is supplied to the first bidirectional shift register from outside, the transfer direction in the first gate means provided at each stage of the first bidirectional shift register is fixed in the reverse direction of the above mentioned first case. In this state, each time after the change of the binary level of the first clock signal with the predetermined cycle, feedback is applied to the first transfer signal by the respective first gate means, and the first transfer signal which has been subjected to the feedback is transferred to the following stage of the first bidirectional shift register. Accordingly, the first bidirectional shift register functions as a unidirectional shift register which has the reverse transfer direction of the first case.
Provided that the first bidirectional shift register is a bidirectional shift register composed of even number of output stages, the first transfer signal, which is output from the first output stage (e.g. the leftmost or rightmost output stage) of the first bidirectional shift register would be inverted according as whether the transfer direction is the forward direction or the reverse direction. For this reason, in order to actually reverse the transfer direction, it is not sufficient to merely change the binary level of the first directional control signal; it is also required to invert the first clock signal (e.g. to invert the phase). Therefore, it would be necessary to provide a mechanism or control for switching the first clock signal in a picture signal processing IC or the like, resulting in a marked disadvantage in constitution and control of the apparatus.
In the present invention, however, the data line driving means in particular comprises a first bidirectional shift register which has odd number of output stages. Hence, regardless of whether the transfer direction is forward or reverse, the transfer signal output from the first output stage (e.g. the leftmost or rightmost output stage) of the first bidirectional shift register will be the same signal. It means that inverting the transfer direction requires only the change of the binary level of the first direction control signal but not requires the inversion of the first clock signal.
Thus, without the need for switching the first clock signal, image signals are sequentially supplied to an odd number of groups of data lines by the data line driving means being in the first direction, which is fixable depending on the first direction control signal level, or in the reverse direction thereof and also being based on the first transfer signal, which is sequentially output from the respective output stages of the first bidirectional shift register.
As a result, according to the driving circuit of the electro-optical apparatus, the horizontal scanning direction of the display image in the liquid crystal device can be easily inverted horizontally merely by changing the level of the first direction control signal.
In order to solve the problems mentioned above, the driving circuit for an electro-optical apparatus is made as a driving circuit for an electro optical apparatus, which has a plurality of data lines to which an image signal is supplied, a plurality of scanning lines to which a scanning signal is supplied, switching means connected to the respective data lines and the respective scanning lines, and a pixel electrode connected to the switching means; and the driving circuit is comprised of a second bidirectional shift register which has an odd number of output stages for supplying a second transfer signal to the scanning lines; wherein each stage of the second bidirectional shift register is fixed in forward direction or reverse direction in accordance with the binary level of a second direction control signal, and the second transfer signal is supplied in sequence from the respective output stages of the second bidirectional shift register in the fixed transfer direction in accordance with of a second clock signal.
According to the driving circuit for the electro-optical apparatus, on one hand, image signals are supplied to the data lines by data line driving means.
On the other hand, regarding scanning line driving means, as a first case, when a second direction control signal having one of the levels of the binary level is applied to the second bidirectional shift register from outside, the transfer direction in a second gate means provided at each stage of the second bidirectional shift register is fixed in the forward direction.(e.g. in the direction from top to bottom) or the reverse direction (e.g. in the direction from bottom to top). In this state, each time after the change of the binary level of the second clock signal with the predetermined cycle, feedback is applied to the second transfer signal by the respective second gate means, and then the second transfer signal which has been subjected to the feedback is transferred to the following stage. Accordingly, the second bidirectional shift register functions as a unidirectional shift register. Contrarily, as a second case, when a second direction control signal having the other level of the binary level is applied to the second bidirectional shift register from outside, the transfer direction in the second gate means provided at each stage of the second bidirectional shift register is fixed in the reverse direction of the aforesaid first case. In this state, each time after the change of the binary level of the second clock signal with the predetermined cycle, feedback is applied to the second transfer signal by the respective second gate means, and the second transfer signal which has been subjected to the feedback is transferred to the following stage. Accordingly, the second bidirectional shift register functions as a unidirectional shift register which has a reverse transfer direction from that in the aforesaid case.
As in the case of the data line driving means as mentioned above, in the present invention, the scanning line driving means is composed of the second bidirectional shift register which has an odd number of output stages. Accordingly, regardless of whether the transfer direction is forward or reverse, the transfer signal output from the first output stage (e.g. the output stage at the top end or the bottom end) of the second bidirectional shift register will be the same signal. This means that inverting the transfer direction requires only the change of the binary level of the second direction control signal but does not require the inversion of the second clock signal.
Thus, without the need for switching the second clock signal, scanning signals are supplied sequentially to the scanning lines by the scanning line driving means being in the second direction, which is fixable depending on the second direction control signal level, or the reverse direction thereof and also being based on the second transfer signal, which is sequentially output from the respective output stages of the second bidirectional shift register.
As a result, according to the driving circuit, the vertical scanning direction of the display image in the liquid crystal device can be easily inverted vertically merely by changing the level of the second direction control signal.
To solve the problems described above, a driving circuit for an electro-optical apparatus is made as a driving circuit for an electro-optical apparatus, wherein a plurality of the data lines are comprised of data line groups, each of which contains a plurality of data lines adjacent each other, wherein the first transfer signal is output in sequence from the respective output stages of the first bidirectional shift register to an odd number of data line groups in the transfer direction of the first direction or the reverse direction of the first direction, and image signal is supplied in sequence for each data line groups based on the first transfer signal.
According to the driving circuit of the electro-optical apparatus, data line driving means is composed of the first bidirectional shift register which has an odd numbered output stages. Hence, regardless whether the transfer direction is forward the reverse, the transfer signal output from the first output stage (e.g. the leftmost or rightmost output stage) from the first bidirectional shift register will be the same signal. This means that inverting the transfer direction requires only the change of the binary level of the first direction control signal but does not require the inversion of the first clock signal. As a result, the horizontal scanning direction in a liquid crystal device can be easily inverted horizontally merely by changing the levels of the first and the second direction control signals.
To solve the problems mentioned above, a driving circuit for an electro-optical apparatus is made as a driving circuit for the electro-optical apparatus, wherein the pulse width of the first transfer signal output from an odd-numbered stage of the first bidirectional shift register is determined to be the same as a predetermined first pulse width by a first waveform selector circuit, while the pulse width of the first transfer signal output from an even-numbered stage of the first bidirectional shift register is determined to be a same as a predetermined second pulse width by a second waveform selector circuit.
According to the driving circuit for the electro-optical apparatus, the pulse width of the first transfer signal output from an odd-numbered stage of the first bidirectional shift register is restricted to the pulse width of the first waveform select signal by the first waveform selector circuit provided for each odd-numbered stage. On the other hand, the pulse width of the first transfer signal output from an even-numbered stage of the first bidirectional shift register is restricted to the pulse width of the second waveform select signal by the second waveform selector circuit provided for the even-numbered stage. Hence, an appropriate time interval is allowed between the image signals which are supplied at about the same time to adjoining groups of data lines. This makes it possible to prevent the problem in which those image signals overlap, especially in a high-frequency drive environment, and ghosts or uneven images occurs resulting from the preceding image signal components which have been written.
Moreover, the data line driving means has an odd number of the first bidirectional shift registers; therefore, inverting the transfer direction requires only the change of the binary level of the first direction control signal but does not require the inversion of the first clock signal or the first and the second waveform select signals.
To solve the problems mentioned above, a driving circuit for an electro-optical apparatus is made as a driving circuit for the electro-optical apparatus, wherein the first waveform selector circuit includes a first logic circuit which takes the AND or exclusive AND of the first transfer signal and the first waveform select signal, while the second waveform selector circuit includes a second logic circuit which takes the AND or exclusive AND of the first transfer signal and the second waveform select signal.
According to the driving circuit for the electro-optical apparatus, the pulse width of the first transfer signal output from an odd-numbered stage of the first bidirectional shift register is restricted to the pulse width of the first waveform select signal by the first logic circuit provided for each odd-numbered stage. Likewise, the pulse width of the first transfer signal output from an even-numbered stage of the first bidirectional shift register can be restricted to the pulse width of the second waveform select signal by the second logic circuit provided for each even-numbered stage.
To solve the problems mentioned above, a driving circuit for an electro-optical apparatus is made as a driving circuit for the electro-optical apparatus, wherein the transition of the pulse waveforms of the first and the second waveform select signals is not rectangular.
According to the driving circuit for the electro-optical apparatus, since the transition of the pulse waveforms of the first and the second waveform select signals are made to be non-rectangular, it is possible to prevent the signal components of the waveform selections signals from being written as noises into the image signals.
To solve the problems mentioned above, a driving circuit for an electro-optical apparatus is made as a driving circuit for the electro-optical apparatus, wherein the transition of the pulse waves is made to be non-rectangular in the range between 20 ns and 50 ns.
According to the driving circuit for the electro-optical apparatus, since the transition of the pulse waves is not rectangular and is not rectangular and is slopped in the range between 20 ns and 50 ns, it is possible to securely prevent the signal components of the waveform select signals from being written as noises into the image signal lines.
To solve the problems mentioned above, a driving circuit for an electro-optical apparatus is made as a driving circuit for the electro-optical apparatus, wherein at least either the first or the second bidirectional shift register includes: a first clocked inverter which can be transferred when the binary level of the first of the second direction transfer signal is at one level and fixes the transfer direction of the first and the second direction transfer signal in the forward direction; a second clocked inverter which can be transferred when the binary level of the first or the second direction transfer signal is at the other certain level and fixes the transfer direction of the first and the second direction transfer signal in the reverse direction, a third clocked inverter which, when the transfer direction of the first and the second direction transfer signal is fixed in the forward direction, transfers the first or second transfer signal, transferred via the first clocked inverter each time after the change of the binary level of the first or the second clock signal, and which, when the transfer direction of the first and the second direction transfer signal is fixed in the reverse direction, applies feedback to the first or the second transfer signal transferred via the second clocked inverter, each time after the change of the binary level of the first or the second clock signal, and a fourth clocked inverter which, when the transfer direction of the first and the second direction transfer signal is fixed in the reverse direction, transfers the first or second transfer signal transferred via the second clocked inverter each time after the change of the binary level of the first or the second clock signal, and which, when the transfer direction of the first and the second direction transfer signal is fixed in the forward direction, applies feedback to the first or the second transfer signal transferred via the first clocked inverter, each time after the change of the binary level of the first or the second clock signal.
According to the driving circuit for the electro-optical apparatus, when the binary level of the first or the second direction control signal is at one level, the transfer direction is fixed in the forward direction by the first clocked inverter which can transfer at that time. When the transfer direction is fixed in the forward direction like this, the first or the second transfer signal transferred via the first clocked inverter is transferred by the third clocked inverter each time after the change of the binary level of the first or the second clock signal. Feedback is applied, by the fourth clocked inverter, to the first or the second transfer signal transferred via the first clocked inverter, each time after the change of the binary level of the first or second clock signal.
Conversely, when the binary level of the first or second direction control signal is at the other level, the transfer direction is fixed in the reverse direction by the second clocked inverter which can transfer at that time. When the transfer direction is fixed in the reverse direction like this, feedback is applied by the third clocked inverter to the first or second transfer signal, which is transferred via the second clocked inverter, each time after the change of the binary level of the first or the second clock signal. And the first or the second transfer signal, which is transferred via the second clocked inverter, is transferred by the fourth clocked inverter each time after the change of the binary level of the first or the second clock signal.
Hence, the first or the second bidirectional shift register constituted as described above functions as a unidirectional shift register having forward or reverse transfer directions, which is determined depending on the binary level of the first or the second direction control signal.
To solve the problems mentioned above, a driving circuit for an electro-optical apparatus is made as a driving circuit for the electro-optical apparatus, wherein at least either the first or the second bidirectional shift register includes: a first transmission gate which can perform transfer and fix the transfer direction in the forward direction when the binary level of the first or the second direction control signal is at one level; a second transmission gate which permits transfer and fixes the transfer direction in the reverse direction when the binary level of the first or the second direction control signal is at the other level, a first clocked inverter which, when the transfer direction is fixed in the forward direction, transfers the first or the second transfer signal transferred via the first transmission gate, each time after the change of the binary level of the first or second clock signal, and which, when the transfer direction is fixed in the reverse direction, transfers the first or the second transfer signal transferred via the second transmission gate, each time after the change of the binary level of the first or the second clock signal, and a second clocked inverter which, when the transfer direction is fixed in the forward direction, applies feedback to the first or the second transfer signal transferred via the first transmission gate, each time the binary level of the first or the second clock signal is switched, and which, when the transfer direction is fixed in the reverse direction, applies feedback to the first or the second transfer signal transferred via the second transmission gate, each time the binary level of the first or second clock signal is switched.
According to the driving circuit for the electro-optical apparatus, when the binary level of the first or second direction control signal is at one level, the transfer direction is fixed in the forward direction by the first transmission gate which enables transfer at that time. When the transfer direction is fixed in the forward direction, the first or the second transfer signal transferred via the first transmission gate is transferred by the first clocked inverter each time the binary level of the first or the second clock signal is switched. Feedback is applied, by the second clocked inverter, to the first or the second transfer signal transferred via the first transmission gate, each time the binary level of the first or the second clock signal is switched.
Conversely, when the binary level of the first or the second direction control.signal is at the other level, the transfer direction is fixed to the reverse direction by the second transmission gate which enables transfer at that time. When the transfer direction is fixed to the reverse direction, the first or the second transfer signal transferred via the second transmission gate is transferred by the first clocked inverter each time the binary level of the first or the second clock signal is switched. Feedback is applied by the second clocked inverter to the first or the second transfer signal, which is transferred via the second transmission gate, each time the binary level of the first or the second clock signal is switched.
Hence, the first or the second bidirectional shift register constituted as described above functions as a unidirectional shift register wherein the forward or reverse transfer direction is determined according to the binary level of the first or the second direction control signal.
Further, the use of the transmission gates obviates the need for routing a power supply, therefore, using the transmission gates for controlling the transfer direction of the bidirectional shift register enables the layout area of the bidirectional shift register to be reduced. This in turn makes it possible to realize a smaller electro-optical apparatus.
To solve the problems mentioned above, a driving circuit for an electro-optical apparatus is made as a driving circuit for the electro-optical apparatus, wherein at least one of the first and the second bidirectional shift register includes: a first transmission gate which enables transfer and fixes the transfer direction in the forward direction when the binary level of the first or the second direction control signal is at one level, a second transmission gate which enables transfer and fixes the transfer direction in the reverse direction when the binary level of the first or the second direction control signal is at the other level; a third transmission gate which, when the transfer direction is fixed to the forward direction, transfers the first or the second transfer signal, which is transferred via the first transmission gate, each time the binary level of the first or the second clock signal is switched, and which, when the transfer direction is fixed in the reverse direction, transfers the first or the second transfer signal, which is transferred via the second transmission gate, each time after the change of the binary level of the first or the second clock signal, and a fourth transmission gate which, when the transfer direction is fixed in the forward direction, applies feedback to the first or the second transfer signal, which is transferred via the first transmission gate, each time the binary level of the first or the second clock signal is switched, and which, when the transfer direction is fixed in the reverse direction, applies feedback to the first or the second transfer signal, which is transferred via the second transmission gate, each time the binary level of the first or the second clock signal is switched.
According to the driving circuit for the electro-optical apparatus, when the binary level of the first or the second direction control signal is at one level, the transfer direction is fixed in the forward direction by the first transmission gate which permits transfer at that time. When the transfer direction is fixed in the forward direction, the first or the second transfer signal transferred via the first transmission gate is transferred by the third transmission gate each time the binary level of the first or the second clock signal is switched. Feedback is applied to the first or the second transfer signal, which is transferred via the first transmission gate, by the fourth transmission gate each time the binary level of the first or the second clock signal is switched.
Conversely, when the binary level of the first or the second direction control signal is at the other level, the transfer direction is fixed to the reverse direction by the second transmission gate which enables transfer at that time. When the transfer direction is fixed to the reverse direction, the first or the second transfer signal, which is transferred via the second transmission gate, is transferred by the third transmission gate each time the binary level of the first or the second clock signal is switched. Feedback is applied to the first or the second transfer signal, which is transferred via the second transmission gate, by the fourth transmission gate each time the binary level of the first or the second clock signal is switched.
Hence, the first or the second bidirectional shift register constituted as described above functions as a unidirectional shift register wherein the forward or reverse transfer direction is determined according to the binary level of the first or the second direction control signal.
The use of the transmission gates obviates the need for routing a power supply, therefore, using the transmission gates for the elements constituting the bidirectional shift register enables the layout area of the bidirectional shift register to be reduced. This in turn makes it possible to realize a smaller electro-optical apparatus.
To solve the problems mentioned above, a driving circuit for an electro-optical apparatus is made as a driving circuit for the electro-optical apparatus, wherein at least one of the first to the fourth clocked inverters is replaced by a transmission gate and an inverter.
According to the driving circuit for the electro-optical apparatus, the transmission gate and inverter, which substitute for at least one of the first to fourth clocked inverters, fix the transfer direction in the forward direction or the reverse direction, or transfer the first or the second transfer signal, or apply feedback to the first or the second transfer signal. Hence, the first or the second bidirectional shift register constituted as described above functions as a unidirectional shift register wherein the forward or reverse transfer direction is determined according to the binary level of the first or the second direction control signal.
Moreover, the use of the transmission gates obviates the need for routing a power supply, therefore, using the transmission gates for the elements constituting the bidirectional shift register enables the layout area of the bidirectional shift register to be reduced. This in turn makes it possible to realize a smaller electro-optical apparatus.
To solve the problems mentioned above, a driving circuit for an electro-optical apparatus is made as a driving circuit for the electro-optical apparatus, wherein at least one of the first to the fourth transmission gates is replaced by a p-channel thin film transistor or an n-channel thin film transistor.
According to the driving circuit for the electro-optical apparatus, by substituting the p-channel thin film transistor or the n-channel thin film transistor for at least one of the first to the fourth transmission gates, the transfer direction is fixed in the forward direction or the reverse direction, or the first or the second transfer signal is transferred, or feedback is applied to the first or the second transfer signal. Hence, the first or the second bidirectional shift register constituted as described above functions as a unidirectional shift register having forward or reverse transfer directions, which is determined depending on the binary level of the first or the second direction control signal.
Moreover, the use of the p-channel thin film transistor or the n-channel thin film transistor reduces the number of the elements to half as compared with using the transmission gates, therefore, using the p-channel thin film transistor or the n-channel thin film transistor for the elements constituting the bidirectional shift register enables the layout area of the bidirectional shift register to be further reduced. This in turn makes it possible to realize a very small electro-optical apparatus.
To solve the problems described above, a driving circuit for an electro-optical apparatus is made as a driving circuit for an electro-optical apparatus which has a plurality of data lines to which an image signal is supplied, a plurality of scanning lines to which a scanning signal is supplied, a switching means connected to the respective data lines and the respective scanning lines, and a pixel electrode connected to the switching means; and the driving circuit is comprised of a sampling circuit for sampling the image signal and supplying it to the data lines, a shift register for supplying a first transfer signal in accordance with a first clock signal, and a plurality of waveform selector circuits which supply a sampling circuit drive signal to the sampling circuit in accordance with the input of the first transfer signal from the shift register and either first and second waveform select signals; wherein the waveform select signals of the first and the second waveform select signals which are different from each other are supplied to adjoining waveform selector circuits, and the pulse of the first waveform select signal is not issued at the same time with the pulse of the second waveform select signal.
According to the driving circuit for the electro-optical apparatus, an appropriate time interval is allowed between the first and the second waveform select signals supplied to adjoining waveform selector circuit, hence, it is possible to prevent ghosts or uneven images caused by the write-in of the image signal components due to the overlap of the image signals. This is especially effective in a high-frequency drive environment.
To solve the problems mentioned above, a driving circuit for an electro-optical apparatus is made as a driving circuit for the electro-optical apparatus, wherein the first waveform selector circuit includes a first logic circuit which takes AND or exclusive AND of the first transfer signal and the first waveform select signal.
According to the driving circuit for the electro-optical apparatus, the pulse width can be restricted to a predetermined pulse width since the first logic circuit which takes AND or exclusive AND of the first transfer signal and the first waveform select signal is included.
To solve the problems mentioned above, a driving circuit for an electro-optical apparatus is made as a driving circuit for the electro-optical apparatus, wherein the transition of the first and the second waveform select signals is not rectangular.
According to the driving circuit for the electro-optical apparatus, by making the pulses non-rectantular, the ringing of the waveform select signal itself can be suppressed, and it is possible to prevent the signal components of the waveform select signals from being written as noises into the image signals.
To solve the problems described above, a driving circuit for an electro-optical apparatus is made as a driving circuit for an electro-optical apparatus, which has a plurality of data lines to which an image signal is supplied, a plurality of scanning lines to which a scanning signal is supplied, switching means connected to the respective data lines and the respective scanning lines, and a pixel electrode connected to the switching means, and the driving circuit comprising a sampling circuit for sampling the image signal and supplying it to the data lines, a shift register for supplying a first transfer signal in accordance with a first clock signal, and a plurality of waveform selector circuits which supply a sampling circuit drive signal to the sampling circuit in accordance with the input of the first transfer signal from the shift register and either two waveform select signals, wherein the pulse width of the waveform select signal is narrower than the pulse width of the first clock signal.
According to the driving circuit for the electro-optical apparatus, an appropriate time interval is allowed between the image signals, which are supplied to the adjoining data lines or the groups of data lines almost at the same time, hence, it is possible to prevent ghosts or uneven images caused by the write-in of image signal components due to the overlap of image signals. This is especially effective in a high-frequency drive environment.
To solve the problems mentioned above, a driving circuit for an electro-optical apparatus is made as a driving circuit for an electro-optical apparatus, which has a plurality of data lines to which an image signal is supplied, a plurality of scanning lines to which a scanning signal is supplied, a switching means connected to the respective data lines and the respective scanning lines, and a pixel electrode connected to the switching means; and the driving circuit is comprised of a sampling circuit for sampling the image signal and supplying it to the data lines, a shift register for supplying a first transfer signal in accordance with the first clock signal, and a plurality of waveform selector circuits which supply the sampling circuit drive signal to the sampling circuit in accordance with the input of the first transfer signal from the shift register and a waveform select signal, wherein the transition of the pulse waveform of the waveform select signal is not rectangular.
According to the driving circuit for the electro-optical apparatus, by making the pulse waveforms non-rectangular, the ringing of the waveform select signal itself can be suppressed, and it is possible to prevent the signal components of the waveform select signals from being written as noises into the image signal lines.
To solve the problems mentioned above, a driving circuit for an electro-optical apparatus is made as a driving circuit for the electro-optical apparatus, wherein the transition of the pulse waves is not rectangular and is not rectangular and is slopped in the range from 20 ns to 50 ns.
According to the driving circuit for the electro-optical apparatus, it is possible to securely prevent the signal components of the waveform select signals from being written as noises into the image signals.
To solve the problems mentioned above, a driving method for an electro-optical apparatus is made as a driving method for an electro-optical apparatus which has a plurality of data lines to which an image signal is supplied, a plurality of scanning lines to which a scanning signal is supplied, a switching means connected to the respective data lines and the respective scanning lines, and a pixel electrode connected to the switching means, and the method is comprised of a step for sampling the image signal according to a sampling control signal which has a pulse width narrower than the pulse width of the first clock signal and supplying it to the data lines, and a step for supplying the sampled image signal via the data lines to the switching means, which is connected to the selected scanning line, while selecting said scanning lines.
According to the driving method for the electro-optical apparatus, an appropriate time interval is allowed between the image signals, which are supplied almost at the same time to the adjoining data lines or the groups of data lines, by the sampling control signal which has the narrower pulse width than the pulse width of the first clock signal, hence, it is possible to prevent ghosts or uneven images caused by the write-in of image signal components due to the overlap of image signals. This is especially effective in a high-frequency drive environment.
To solve the problems described above, a driving method for an electro-optical apparatus has been made as a driving method for an electro-optical apparatus which has a plurality of data lines to which an image signal is supplied, a plurality of scanning lines to which a scanning signal is supplied, a switching means connected to the respective data lines and the respective scanning lines, and a pixel electrode connected to the switching means; and the driving method is comprised of a step for sampling the image signal in accordance with a first transfer signal from a shift register and a sampling circuit drive signal based on the input of either first and second waveform select signals and then supplying it to the data lines, and a step for supplying the sampled image signal via the data lines to the switching means, which is connected to the selected scanning line, while selecting the scanning lines, wherein the first and the second waveform select signals are alternately issued in other words, not issued at the same time.
According to the driving method for the electro-optical apparatus, the image signals are sampled by the sampling circuit driving signals, which are based on the first and second waveform select signals which are issued alternately and not overlapped with each other from the first and second waveform select signal lines to adjoining data lines or groups of data lines. Subsequently the sampled signal is supplied to the data lines. Hence it is possible to protect the data lines from the ghosts or uneven images caused by the write-in of image signal components due to the overlap of image signals. This is especially effective in a high-frequency drive environment.
To solve the problems described above, a driving circuit for an electro-optical apparatus is a driving circuit for an electro-optical apparatus which has a plurality of data lines to which an image signal is supplied, a plurality of scanning lines to which a scanning signal is supplied, a switching means connected to the respective data lines and the respective scanning lines, and a pixel electrode connected to the switching means, and the driving method is comprised of a step for supplying a sampling circuit drive signal to a sampling circuit in accordance with the input of a first clock signal and a waveform select signal, a step for sampling the image signal in accordance with the sampling control signal and supplying it to the data lines, and a step for supplying the sampled image signal via the data lines to the switching means connected to the selected scanning line, while selecting said scanning lines, wherein the transition of the pulse waveform of the waveform select signal being nonrectangular.
According to the driving circuit for the electro-optical apparatus, by making the transition of the pulse waveform non-rectangular, the ringing of the waveform select signal itself can be suppressed, and further it is possible to prevent the signal component of the waveform select signal from being written as a noise into the image signal.
To solve the problems described above, in a driving circuit for an electro-optical apparatus, the transition of the pulse waveform of the waveform select signal is not rectangular and is slopped in the range from 20 ns to 50 ns.
According to the driving circuit for the electro-optical apparatus, it is possible to securely prevent the signal component of the waveform select signal from being written as a noise into the image signal line.
To solve the problems described above, an electro-optical apparatus is equipped with a driving circuit for an electro-optical apparatus.
According to the electro-optical apparatus, it is possible to vertically or horizontally invert the scanning direction in accordance with, for example, the binary level of a first or a second direction control signal. Moreover, it is also possible to protect the data lines from ghosts or uneven images caused by the written-in of the image signal components due to overlap of the image signals.
To solve the problems described above, an electronic apparatus is equipped with the electro-optical apparatus.
According to the electronic apparatus, the aforementioned electro-optical apparatus in accordance with the present invention is included in the electronic apparatus, and the scanning direction on a display screen can be inverted both vertically and horizontally and a display free from uneven images or ghosts can be provided.
The operations and other advantages of the present invention as described above will be made apparent by the embodiments to be given below.